Abstract: Dry corn straw (DCS) and cabbage waste (CW) were mixed and ensiled trans-seasonally; the effect of cellulase addition on silage quality and microbial community diversity were assessed. Three treatments were compared; a control (ME) (no cellulase), 0.1% cellulase (CA) and 0.3% cellulase (CB). All silages were ensiled for 60 days in airtight containers. Chemical composition and fermentation quality were measured over a 30 day period. Microbial community diversity was analyzed using Miseq high-throughput sequencing technologies. The results showed that neutral detergent fiber (NDF), acid detergent fiber (ADF) and cellulose (CL) in groups CA and CB were significantly lower than ME after 30 days (P<0.05); pH and ammonia nitrogen to total nitrogen ratio (AN/TN) were also significantly lower than ME after 30 days (P<0.05). Lactic acid (LA) and water soluble carbohydrates (WSC) were significantly higher than the ME treatment (P<0.05). Lactic acid to acetic acid ratio’s (LA/AA) were greater than 3 and LA to total organic acid ratio’s (LA/TOA) were greater than 0.6 for all treatments after 60 days, but fermentation intensity was highest in the CB treatment. The microbial community diversity results showed that Firmicutes and Proteobacteria were dominant at the phylum level, the dominant microflora at the genus level were Paralactobacillus, Lactobacillus and Enterobacter. Over time, the abundance of Enterobacter gradually decreased and the abundance of Paralactobacillus and Lactobacillus increased, which indicated that the addition of cellulase improved the abundance of lactic acid bacteria and reduced the abundance of spoilage bacteria. It was concluded that low cellulase (0.1%) was the most appropriate application rate; it was conducive to the preservation of hemicellulose (HC), CL and WSC and improved fermentation quality.

Key words: dry corn straw, cabbage waste, cellulase, mixed storage quality, microbial community diversity